In the past, when installing a camera module on printed circuit board arranged inside electronic equipment such as a portable telephone, and the like, camera modules susceptible to heat could not by installed by direct soldering. Therefore, a socket for installing electronic parts was used and connected to the printed circuit board.
The main socket for installing electronic parts connected a camera module to a connecting substrate through contacts by: providing a socket housing, which had an electronic part receptor upwardly facing and including by a bottom base part and a peripheral wall constituting front, rear, right and left standing walls standing around the periphery of the bottom base part, and a plurality of contacts supported in the socket housing. The flexible contact pieces are provided as a single unit with the contacts protruding to the inner surface of the electronic part receptor. By inserting a camera module into the electronic part receptor, the terminals of the camera module and the flexible contact pieces contact (for example, see Japanese Unexamined Laid-Open Patent Application No. 2007-26765 (“the '765 application”), No. 2005-268020 (“the '020 application”) and No. 2005-276626 (“the '626 application)).
Alternatively, as connection substrate and socket contact connection systems, there exist systems that expose contact substrate side connection terminals at the bottom surface of a housing, and surface mount this housing to the substrate by soldering to printed circuit pattern terminals (for example, see the '765 application and the '020 application); and systems that provide a flange-shaped extension part in a single unit at a position of intermediate height on the periphery of the housing and provide on the substrate an opening in which a part lower than a support part of the housing is inserted. A pattern terminal is provided on the peripheral part of that opening; and mounts by inserting substantially the lower half of the aforementioned housing into an opening in the substrate. Substrate connection terminals of contacts exposed to the lower surface of the extension part are soldered to pattern terminals on the substrate (for example, see the '626 application).
Moreover, as a contact accommodation system in relation to the housing, to make the flexible contact pieces of the contacts have a more satisfactory force of elastic deformation requires that the flexible contact pieces have long parts capable of elastic deformation. For that reason, in the past, the flexible contact pieces have been formed in a single unit through a flexed part bent back in a U-shape in relation to the support part that supports the contacts in relation to the housing.
Systems to accommodate this support part and flexed part may accommodate these parts inside the thickness of a bottom plate that includes the electronic part receptor of the housing (see, e.g., the '020 application), and systems that accommodate these parts within the peripheral wall of the same (see, e.g., the '765 application).
In the conventional examples described above, the system of mounting by inserting the lower side of the housing into the connection substrate (as in the '626 application) lowers the installation height in relation to the substrate of the socket substrate more than does the system of soldering the connection terminals exposed at the bottom surface of the housing to pattern terminals of the surface of the substrate. However, there is the disadvantage that the surface area occupied by the surface of the substrate becomes broader because the substrate connecting terminals are exposed on the low surface of the expansion part that extends in a flange-shape at the body of the housing.
Conversely, the system of soldering the substrate connection terminals exposed to the bottom surface of the housing to the pattern terminals on the substrate surface (as in the '765 application and the '020 application) requires a smaller substrate surface area as compared to the system of mounting by inserting the lower side of the housing into the connecting substrate, but there is the disadvantage that the installation height in relation to the substrate is high.
Moreover, the system of accommodating in the peripheral wall thickness the support part and the flexed part folded back in a U-shape (as in the '626 application) lowers the installation height in relation to the substrate surface more than does the system of accommodation in the bottom plate thickness, but has the disadvantage that the horizontal width and the surface area occupied on the substrate surface are enlarged. Conversely, however, the system of accommodation in the bottom plate thickness makes for a smaller horizontal width and less surface area occupied on the substrate surface than does the system that accommodates in the peripheral wall thickness, but the installation height in relation to the substrate surface is higher.